Research On Operating Time Window And Slot Allocation For Export And Import Containers

Container Terminal is an important node of the cargo transportationconnecting continent and marine transportation and the largest distributioncenter of goods throughout the transport chain. Container terminal is the hub ofcontainer transport system, which uses its space resources (including berths,container yards, warehouses, anchorages) and equipment (including loadingand unloading equipment, transportation equipment, etc.) to provide servicesfor shippers and container ships by operating container loading, unloading andtransporting. Facing the increasing cargo throughput and limited spaceresources, as well as the intensifying competition from service-orientedterminals, major ports are dedicated to the scientific management andoptimization of the operation of the terminals. Study on how to improve theoperations efficiency of the port and provide customers with the highestquality service through optimization of the resources utilization is of greatimportance.To improve space resources utilization and operational efficiency of theport, this article firstly explored the time window management to facilitatedelivering operations of export containers which is widely used Chineseterminals. Considering the work balance of terminal gate in different time slotsand space resources utilization which are the key factors affecting the overallservice quality of the port, an optimizing model was suggested to allocate timewindows for delivering export containers in a rolling horizon. Finally, themodel and the heuristic algorithm were tested, and the result indicated thatoptimization of the time window can effectively flatten the peak amount ofexport containers arriving across the planning period, thus improve resourcesutilization and lower the amount of time spent by the export container trucks waiting for service at the terminal gate at the same time.The article further studied on how to optimize the sequence and time forcustomers to fetch the containers stacked in the yard to minimize the expectednumber of rehandles during the fetching operation. An incentive mechanismwas suggested to impact the arriving sequence and time of the trucks and lowerthe uncertainty which together causes the rehandles. Based on the mechanism,a mathematical model was constructed and genetic algorithm was applied tosolve the problem. Results showed when incentive parameters were setproperly, the model can lower the rehandle rate and maintain the benefits ofboth parties. Further sensitivity analysis also showed that the new timewindow assign system can exert a greater impact on the reducing rehandleswhen stacking layers increases.